Skip to content

Commit

Permalink
Normalize the function signature of closures
Browse files Browse the repository at this point in the history
Previously we didn't normalize the function signatures used for
closures. This didn't cause a problem in most cases, but caused an ICE
in during MIR type checking.

Fixes rust-lang#36139
  • Loading branch information
Aatch committed Aug 31, 2016
1 parent eac4146 commit e0279d7
Show file tree
Hide file tree
Showing 3 changed files with 36 additions and 1 deletion.
7 changes: 6 additions & 1 deletion src/librustc_typeck/astconv.rs
Original file line number Diff line number Diff line change
Expand Up @@ -1877,11 +1877,16 @@ impl<'o, 'gcx: 'tcx, 'tcx> AstConv<'gcx, 'tcx>+'o {
hir::DefaultReturn(..) => self.tcx().mk_nil(),
};

let input_tys = self_ty.into_iter().chain(arg_tys).collect();

debug!("ty_of_method_or_bare_fn: input_tys={:?}", input_tys);
debug!("ty_of_method_or_bare_fn: output_ty={:?}", output_ty);

(self.tcx().mk_bare_fn(ty::BareFnTy {
unsafety: unsafety,
abi: abi,
sig: ty::Binder(ty::FnSig {
inputs: self_ty.into_iter().chain(arg_tys).collect(),
inputs: input_tys,
output: output_ty,
variadic: decl.variadic
}),
Expand Down
2 changes: 2 additions & 0 deletions src/librustc_typeck/check/closure.rs
Original file line number Diff line number Diff line change
Expand Up @@ -74,6 +74,8 @@ impl<'a, 'gcx, 'tcx> FnCtxt<'a, 'gcx, 'tcx> {

let fn_sig = self.tcx.liberate_late_bound_regions(
self.tcx.region_maps.call_site_extent(expr.id, body.id), &fn_ty.sig);
let fn_sig =
(**self).normalize_associated_types_in(body.span, body.id, &fn_sig);

check_fn(self, hir::Unsafety::Normal, expr.id, &fn_sig, decl, expr.id, &body);

Expand Down
28 changes: 28 additions & 0 deletions src/test/run-pass/issue-36139-normalize-closure-sig.rs
Original file line number Diff line number Diff line change
@@ -0,0 +1,28 @@
// Copyright 2016 The Rust Project Developers. See the COPYRIGHT
// file at the top-level directory of this distribution and at
// http://rust-lang.org/COPYRIGHT.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.

// Previously the closure's argument would be inferred to
// <S as ITrait<'a>>::Item, causing an error in MIR type
// checking

trait ITrait<'a> {type Item;}

struct S {}

impl<'a> ITrait<'a> for S { type Item = &'a mut usize; }

fn m<T, I, F>(_: F)
where I: for<'a> ITrait<'a>,
F: for<'a> FnMut(<I as ITrait<'a>>::Item) { }


fn main() {
m::<usize,S,_>(|x| { *x += 1; });
}

0 comments on commit e0279d7

Please sign in to comment.